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A team of telescopes around the world will be focusing on the faint signal of the space probe Huygens as it dives into Saturn's moon Titan in January.

The telescopes, which include five radio telescopes in Australia, will track the European Space Agency's probe and will measure the effect of wind catching the probe's parachute as it falls through the thick atmosphere of Saturn's largest moon.

The orbiting NASA spacecraft Cassini will release the Huygens probe at 02:00 UTC on 25 December (13:00 AEST), arriving at the edges of Titan's atmosphere on 14 January 2005.

Cassini will send most of the probe's signals back to Earth. But Cassini must turn its antenna back to Earth to beam back the information.

During the time Cassini is turned away from the probe the Earth-based telescopes will try and pick up the probe's weak signal.

They will use a technique called very long baseline interferometry, which the ESA said would allow researchers to measure the probe's trajectory with an unprecedented accuracy of one kilometre.

He said the signal would be as weak as trying to pick up a mobile phone call on Venus from Earth.

"This particular experiment is trying to pinpoint the position as the probe enters the atmosphere," Phillips told ABC Science Online.

Later the data would be combined to create very high-resolution images of the probe, he said.

Listening to the wind

The main job of the telescopes, including two University of Tasmania telescopes, is to track the position of the probe as it moved across the sky.

But the large dish at Parkes will also gauge the distance of the probe by measuring its doppler shift, the shift in wavelength as the probe gets further and further away.

This will reveal the depth of the probe as it sinks into Titan's nitrogen-rich atmosphere.

It will also reveal any sideways motion as the wind catches the probe's parachute.

"If we see a strong sideways motion that's due to the effect of the counter motion of wind formed as the moon rotates," said Phillips.

"It's quite a thick atmosphere so you would expect quite strong winds."

While telescopes on Earth had previously measured Titan's winds, no one knows exactly how the winds will affect the probe.

Australian planetary scientist Dr Simon Ellis from the Anglo-Australian Observatory said Titan's winds are formed the same way as winds on Earth.

He said there had been concerns when Huygens was launched that the probe could be damaged by Titan's winds and thick atmosphere.

During its descent and landing Huygens' instruments will photograph the moon, sample the atmosphere and determine any physical characteristics of the landing site, which could be ice, water or rock. The probe will also listen for sounds on Titan.